Conventionally, viral diseases have been mainly prevented by the use of virus vaccines. However, vaccines are made specifically for individual viruses and are effective only for such individual viruses. There are numerous kinds of viruses, whereas vaccines are currently put to use against a very limited number of viruses. Moreover, viruses often include many mutant strains, but a vaccine effective against one virus often may not be so against a different virus of the same kind. In addition, it is extremely difficult to develop many vaccines associated with fewer side effects.
On the other hand, various antiviral agents (acyclovir, ganciclovir, Ara-A etc.) have been developed and put to use, but they are effective against an extremely narrow range of viral infections, and there has been found no drug effective against a broad range of viral diseases. These antiviral agents show strong side effects, which prevents general application thereof in clinical situations. In recent years, interferon has been applied to the treatment of viral hepatitis and the like, but side effects, such as fever, occur frequently. While interferon inhibits growth of viruses, there have been found no reports on the direct prevention of cytotoxicity. Gamma globulin has been widely used for the treatment of viral diseases, but its achievement is not necessarily consistent.
2-Aminopropane-1,3-diol compounds including 2-amino-2-(2-(4-octylphenyl)ethyl)propane-1,3-diol hydrochloride are known as a suppressant of rejection in organ or bone marrow transplantation, and as a therapeutic agent of various autoimmune diseases (e.g., psoriasis, Behcet's disease) and rheumatic diseases (WO94/08943).
However, the prior art has never acknowledged effectiveness of a 2-aminopropane-1,3-diol compound for the treatment of viral diseases.